<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Function broadcast</title>
<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset">
<link rel="up" href="../../mpi/reference.html#header.boost.mpi.collectives_hpp" title="Header &lt;boost/mpi/collectives.hpp&gt;">
<link rel="prev" href="all_to_all.html" title="Function all_to_all">
<link rel="next" href="gather.html" title="Function gather">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td>
<td align="center"><a href="../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
<td align="center"><a href="../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="all_to_all.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../mpi/reference.html#header.boost.mpi.collectives_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="gather.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
</div>
<div class="refentry">
<a name="boost.mpi.broadcast"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2><span class="refentrytitle">Function broadcast</span></h2>
<p>boost::mpi::broadcast — Broadcast a value from a root process to all other processes. </p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../mpi/reference.html#header.boost.mpi.collectives_hpp" title="Header &lt;boost/mpi/collectives.hpp&gt;">boost/mpi/collectives.hpp</a>&gt;

</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> 
  <span class="keyword">void</span> <span class="identifier">broadcast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="communicator.html" title="Class communicator">communicator</a> <span class="special">&amp;</span> comm<span class="special">,</span> <span class="identifier">T</span> <span class="special">&amp;</span> value<span class="special">,</span> <span class="keyword">int</span> root<span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> 
  <span class="keyword">void</span> <span class="identifier">broadcast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="communicator.html" title="Class communicator">communicator</a> <span class="special">&amp;</span> comm<span class="special">,</span> <span class="identifier">T</span> <span class="special">*</span> values<span class="special">,</span> <span class="keyword">int</span> n<span class="special">,</span> <span class="keyword">int</span> root<span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> 
  <span class="keyword">void</span> <span class="identifier">broadcast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="communicator.html" title="Class communicator">communicator</a> <span class="special">&amp;</span> comm<span class="special">,</span> <a class="link" href="skeleton_proxy.html" title="Struct template skeleton_proxy">skeleton_proxy</a><span class="special">&lt;</span> <span class="identifier">T</span> <span class="special">&gt;</span> <span class="special">&amp;</span> value<span class="special">,</span> 
                 <span class="keyword">int</span> root<span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> 
  <span class="keyword">void</span> <span class="identifier">broadcast</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="communicator.html" title="Class communicator">communicator</a> <span class="special">&amp;</span> comm<span class="special">,</span> <span class="keyword">const</span> <a class="link" href="skeleton_proxy.html" title="Struct template skeleton_proxy">skeleton_proxy</a><span class="special">&lt;</span> <span class="identifier">T</span> <span class="special">&gt;</span> <span class="special">&amp;</span> value<span class="special">,</span> 
                 <span class="keyword">int</span> root<span class="special">)</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.25.7.5.7.4"></a><h2>Description</h2>
<p><code class="computeroutput">broadcast</code> is a collective algorithm that transfers a value from an arbitrary <code class="computeroutput">root</code> process to every other process that is part of the given communicator. The <code class="computeroutput">broadcast</code> algorithm can transmit any Serializable value, values that have associated MPI data types, packed archives, skeletons, and the content of skeletons; see the <code class="computeroutput">send</code> primitive for communicators for a complete list. The type <code class="computeroutput">T</code> shall be the same for all processes that are a part of the communicator <code class="computeroutput">comm</code>, unless packed archives are being transferred: with packed archives, the root sends a <code class="computeroutput"><code class="computeroutput"><a class="link" href="packed_oarchive.html" title="Class packed_oarchive">packed_oarchive</a></code></code> or <code class="computeroutput">packed_skeleton_oarchive</code> whereas the other processes receive a <code class="computeroutput"><code class="computeroutput"><a class="link" href="packed_iarchive.html" title="Class packed_iarchive">packed_iarchive</a></code></code> or <code class="computeroutput">packed_skeleton_iarchve</code>, respectively.</p>
<p>When the type <code class="computeroutput">T</code> has an associated MPI data type, this routine invokes <code class="computeroutput">MPI_Bcast</code> to perform the broadcast.</p>
<p>
</p>
<div class="variablelist"><table border="0" class="variablelist compact">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term">Parameters:</span></p></td>
<td><div class="variablelist"><table border="0" class="variablelist compact">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><code class="computeroutput">comm</code></span></p></td>
<td><p>The communicator over which the broadcast will occur.</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="computeroutput">root</code></span></p></td>
<td><p>The rank/process ID of the process that will be transmitting the value. </p></td>
</tr>
<tr>
<td><p><span class="term"><code class="computeroutput">value</code></span></p></td>
<td><p>The value (or values, if <code class="computeroutput">n</code> is provided) to be transmitted (if the rank of <code class="computeroutput">comm</code> is equal to <code class="computeroutput">root</code>) or received (if the rank of <code class="computeroutput">comm</code> is not equal to <code class="computeroutput">root</code>). When the <code class="computeroutput">value</code> is a <code class="computeroutput"><code class="computeroutput"><a class="link" href="skeleton_proxy.html" title="Struct template skeleton_proxy">skeleton_proxy</a></code></code>, only the skeleton of the object will be broadcast. In this case, the <code class="computeroutput">root</code> will build a skeleton from the object help in the proxy and all of the non-roots will reshape the objects held in their proxies based on the skeleton sent from the root.</p></td>
</tr>
</tbody>
</table></div></td>
</tr></tbody>
</table></div>
</div>
</div>
<div class="copyright-footer">Copyright © 2005-2007 Douglas Gregor,
      Matthias Troyer, Trustees of Indiana University<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at &lt;ulink url="http://www.boost.org/LICENSE_1_0.txt"&gt;
        http://www.boost.org/LICENSE_1_0.txt &lt;/ulink&gt;)
      </p>
</div>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="all_to_all.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../mpi/reference.html#header.boost.mpi.collectives_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="gather.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
</div>
</body>
</html>
